The schedule is a bit tight.
Is it realistic?
Leaving Enniskerry early in the morning
Driving through Wicklow Mountains National Park
Glendalough lakes
Kilkenny (brewery and castle)
Rock of Cashel
Middleton Distillery
Arriving at Killarney in the evening
Thanks
That's 6 hours of driving alone, so yes your proposed itinerary strikes me as being too ambitious...assuming that you actually want to stop and see a few things along the way.
The obvious outlier is Midleton. If you skipped that and just proceeded to Killarney after stopping at Cashel you could probably enjoy the rest of this without running yourselves ragged.
With an early start from Enniskerry you could drive thru the Wicklow Mtns and still arrive at Glendalough well before the tour buses start to roll in at 9:30. Believe me, it's a completely different experience if you're there before the day trippers arrive - you'll have the place pretty much all to yourselves and can explore the monastic settlement, the lakes, and the trails at your leisure. Kilkenny and the Rock of Cashel can then be explored at a much more relaxed pace. You'll still get into Killarney early enough to stop by some of the attractions in the NP, and will probably be able to grab a pint and sit in on a music session at one of the pubs while you're at it.
